Warg

In Norse mythology, a vargr (pl. vargar; often anglicised as warg or varg) is a wolf and in particular refers to the wolf Fenrir and his sons Sköll and Hati. Based on this, J. R. R. Tolkien in his fiction used the Old English form warg (other O.E. forms being wearg and wearh) to refer to a particularly evil kind of wolf.

In Old Norse, is derived from the reconstructed Proto-Germanic *wargaz, ultimately derived from the reconstructed Proto-Indo-European (PIE) root *werg̑ʰ- "destroy". In Beowulf, Grendel's mother is described (line 1514) as a grund-wyrgen, which may be translated as "cursed creature of the depths", "bottom-dwelling monster" etc.

vargr (compare modern Swedish varg "wolf") has arisen as a noa-word for úlfr, the normal Old Norse term for "gray wolf" which is related to similar words in other Indo-European languages and is derived from the reconstructed Proto-Indo-European noun *wĺ̥kʷos ("wolf") and, probably also, the PIE adjective *wl̥kʷós "dangerous". These words comprise *wä́lkʷë, Proto-Italic *lukʷos, Proto-Balto-Slavic *wilkas, Old Albanian ulk, Greek *lýkos, Proto-Iranian *verk Sanskrit vṛka, Avestan vehrka, Mazandarani varg, Zazaki verg, Old Persian varka- and Persian gorg, among others, all meaning "wolf". Despite their superficial similarity to Old Norse vargr, the various Indo-Iranian forms are not related to it but derive from *wĺ̥kʷos.

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